package com.yanti.util;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

/**
 * 获取自增id
 */
@Component
public class RedisIdWorker {
    /**
     * 起始的时间戳
     */
    private static final long BEGIN_TIMESTAMP = 1735689600L;
    /**
     * 序列号的位数
     */
    private static final int COUNT_BITS = 32;
    private final StringRedisTemplate stringRedisTemplate;

    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }
    public long nextId(String keyPrefix) {
        // 生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond - BEGIN_TIMESTAMP;
        // 生成序列号
        // 获取当前日期，精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        Long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
        // 非空检查，避免空指针异常
        if (count == null) {
            count = 0L;
        }
        // 拼接并返回
        return timestamp << COUNT_BITS | count;
    }

//    public static void main(String[] args) {
//        // 打印当前时间
//        LocalDateTime dateTime = LocalDateTime.of(2025, 1, 1, 0, 0, 0);
//        long epochSecond = dateTime.toEpochSecond(ZoneOffset.UTC);
//        System.out.println("timestamp = " + epochSecond);
//    }
}